Chronic kidney disease (CKD) affects 12% of the United States adult population and it doubles the risks for stroke and dementia. While small vessel ischemic disease is linked with both stroke and dementia in the general population, almost nothing is known about the risk factors for small vessel ischemic disease in the brain or the relation of small vessel ischemic disease to clinical outcomes in patients with CKD. We propose to characterize the physiological mechanisms that underlie the relationship between CKD, hypertension, and small vessel ischemic disease in the brain by conducting an ancillary study to SPRINT MIND. The Systolic Pressure INtervention Trial Memory and cognition IN Decreased hypertension (SPRINT MIND) is an NIH sponsored trial testing whether a strategy of lowering systolic blood pressure below current targets reduces incident dementia and brain small vessel ischemic disease. In this application entitled 'MIND the Kidneys', we propose to enrich the neuroimaging component of SPRINT MIND with 170 additional subjects with CKD, and to add novel measures of brain perfusion and perfusion reserve using state-of-the-art Arterial Spin Labeling. Our specific aims complement and substantially extend the core aims of SPRINT MIND by evaluating whether CKD and hypertension therapy affect brain perfusion, and whether changes in brain perfusion correlate with cognitive outcomes. We have assembled a multi-disciplinary group of investigators to address these important and innovative aims.